This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. Although disulfide bonds are well understood for their structural impact, few studies have focused on the necessary distance requirements. Current studies have found that distances as close as a three amino acid chain can intra-molecularly disulfide bond to itself. Empirical computational studies using PQSmol[unreadable] has determined that 3 amino acids are necessary to lower the energy for favorable disulfide bond formation. I would like to determine energy calculations of modified polypeptides.